Category Archive: Airsweep

How Does AirSweep Improve Material Handling Efficiency?

Material in a hopper

The biggest challenge of any factory or plant is material handling efficiency. How can you move massive amounts of material and prevent spoilage and waste? How do you get material to flow properly when it’s mixed and processed? How can you prevent material blocks that can stop production?

The reason material handling efficiency is so difficult is that materials have different flow properties. Some will settle during storage, or segregate when they’re mixed. Others will attract moisture and clump or cake. The sticky and dense formulas also have a tendency to cling to vessel walls and pipes.

Cohesive powders and solutions also present another problem: bridging and ratholing. Once these form in a vessel, the material flow slows down and even stops completely.

AirSweep improves material handling efficiency

Thousands of plants around the world trust AirSweep to solve these problems. AirSweep is a pneumatic flow aid that uses powerful air pulses to break up material blocks and push them back into the flow stream. It’s proven effective for even tough materials that other flow aids can’t handle.

Speed up production

Sluggish material flow affects all downstream processes and increases total production time. In many cases, workers even have to be pulled from other parts of the plant to manually clear the blocks.

Installing AirSweep can significantly speed up production. A minerals processing plant handles 120,000 tons of material a year. However, the powders and pebbles would plug the outlets. It took them an hour to fill just one supersack.

With AirSweep in place, material flowed quickly and reliably—cutting the filling of supersacks from one hour to two minutes. That’s a 3000% increase in production! The company eventually hired more people to keep up with the higher material flow.

Enable product innovation

Companies are always trying to improve their product. However, changing any component in a product formula can introduce new problems in material handling efficiency.

An international paint company needed to use a new grade of titanium dioxide. However, the material, which had finer and lighter particles, had a tendency to bridge above the feeder system and on the pneumatic transport vessels.

When AirSweep was installed in those problematic areas, it was able to clear out blocks and ensure on-demand flow. This reduced the batch time to just 15 minutes.

Reduce material waste

Food industries have to meet very strict regulations on spoilage and contamination. So, poor material flow will often mean throwing away any compromised batches. In fact, a flax company had to toss out 40 pounds of mixture away a day and even have to pay to have it hauled away.

The company tried many flow aids, including vibrators and fluidizers. However, workers still ended up spending an hour each day clearing away clogged material. Poor material handling efficiency was wasting money and time.

After AirSweep, everything changed. The system solved 90% of the material retention problems, reduced waste, and improved production speed.

Ensure plant safety

Safety violations and risks can cost a business its license to operate and lead to thousands of dollars in fines. However, poor material flow can put workers at risk, especially if they have to manually clean out stuck material in a hazardous environment.

One of the world’s largest building materials companies had issues with hot cement clinker plugging up vessels and chutes. Workers had to break up the material with bars and hammers, but this unnecessarily exposed them to chemicals and dust.

After installing AirSweep, they never had issues with clogged clinker. It improved production, but more importantly, ensured the safety of the workers.

AirSweep is proven to improve material handling efficiency

AirSweep is used in every industry and in every continent except Antarctica. Go to our case studies page to find more stories of how it has helped companies increase production, reduce waste, lower cost, and improve product quality and plant safety.

How to Choose the Right Flow Aid for Your Material

Material bridging in a hopper

Flow aids can help clear material bridging in hoppers or any other storage bin, chute, or conveyor. They are relatively inexpensive, and can actually “pay for themselves” because of the increase in productivity.

It’s important to get the right flow aid for your material. The wrong flow aid may not be able to activate the material, or may even cause material blocks to compress even further. Some flow aids also create other problems, like high energy costs or damage to the vessel.

Here is a simple guide to the different flow aids, so you can pick the best one to clear material bridging in a hopper.

Industrial Vibrators

Industrial vibrators use mechanical agitation to improve material flow. The movement breaks a material’s cohesive friction and loosens it from vessel walls. They are sometimes called vibrating dischargers or agitators.

However, vibrators are not very efficient. They can make some materials settle or become compact—think of how you shake the measuring cup to condense brown sugar. That’s fine if you want to bake cookies, but not if you’re trying to achieve material flow in your plant.

That’s what happened to Flax4Life, a commercial bakery that produces gluten-free muffins, brownies, and other baked goods. “The vibrators that came installed on the bottom of the hopper above the mixture practically turned the flax into concrete,” said Stanley Rhea, the maintenance department head.

Vibrators can also still leave residue on vessel walls, which means you still need to do manual cleaning between batch runs. That wastes time and even increases costs. A spice company spent an average of $200,000 just on flushing material for their ribbon blenders.

Finally, industrial vibrators consume a lot of energy, are very noisy, and can cause metal fatigue.

Fluidizers

Fluidizers use a combination of aeration and gentle vibration to activate the material. While these are one of the most inexpensive flow aids (sometimes, they come pre-fitted into storage vessels) they are only effective for light powders like flour.

Fluidizers also have a very small activation radius, so you may need dozens of them to correct material bridging in a hopper. Since the units run continuously, you will have higher energy costs. So, even if it is “cheap” it is not cost-efficient, and you may end up spending more in the long run.

Air cannons

Air cannons release a high-pressure blast of air (typically compressed to 100 PSI) to disperse material.

While air cannons seem powerful, it actually provides limited results. Air tends to “channel” through holes in the material, greatly diminishing effectiveness. It also leaves material residue on the walls and often has “blind spots” where material can still collect. You also cannot control the feed rates.

Air cannons also cause a lot of metal fatigue, and will actually cause damage to the vessels. The loud blasts of noise can also be very stressful for workers, and long term, can cause hearing problems.

AirSweep

AirSweep is a pneumatic flow aid that uses short, powerful pulses to push material back into the flow stream. It can activate any kind of material—even moist, sticky, and heavy powders and solids. It even works on liquid cheese.

Watch this video to see how AirSweep is the most effective solution to material bridging in hoppers:

Many companies switched to AirSweep simply because it worked better than any other flow aid. Flax4Life tried vibrators and fluidizers, and neither of them worked. “AirSweep got a 10/10!” said Stanley Rhea.

Heidelberg Cement, one of the largest building materials companies in the world, also found that AirSweep was more effective than air cannons. “AirSweep worked perfectly!”

Get the right flow aid for your material

We can customize the AirSweep system for your process. We have different models with various activation ranges and a USDA-accepted model for sanitary processes. Our AirSweep Straight Shooter can also release a vertical column of air for chutes or hard-to-reach areas.

Get a free proposal today, and finally solve material bridging in hoppers for good.

3 Ways How to Improve Material Handling

Material flowing on conveyer belt

Poor material handling slows down production, incurs costs, and even creates safety or sanitation hazards that can lead to expensive fines and plant shutdowns. Here are some ways to improve material handling for better efficiency and lower costs.

Evaluate your process

Identify the areas where there is poor material flow. Then, diagnose the causes and the impact of the problem on your productivity and costs. From there, you will have a more concrete idea of how to improve material handling.

For example, a cement company in Asia needed to achieve a flow rate of 30 tons per hour, but could not hit their productivity targets because of shale clogging in the silos. Workers had to manually clear the vessels, which meant stopping the process and pulling teams assigned to other parts of the plant. They calculated that they lost $12,000 for every hour of downtime.

Once the cement company installed AirSweep in the silos, productivity surged and costs went down.

Know your material’s flow properties

Materials have different flow rates and properties that can pose challenges whenever they are stored, transported, and processed. Even changing one material in the formula can lead to unexpected issues during production.

For example, a major international paint and coatings manufacturer needed to use a new grade of Titanium Dioxide (TiO2) to improve their product. The material had finer, lighter particles and had a tendency to bridge over the vibrating feeder system.

They installed AirSweep and designed it to automatically activate when a flow sensor detected bridging in the bottom feeder. This enabled them to cut the batch processing time to just 15 minutes.

Identify risks

One of the best ways to improve material handling is to prevent issues from even occurring. Look at your process and identify possible risks or hazards.

For example, a concrete company uses 12 mixers, with feeders loading up to 250 tons of gravel an hour, or 4 tons a minute. With that amount of gravel, any equipment failure and resulting material pileup would cause safety issues and days of shoveling.

The company installed a DAZIC zero speed switch that would trigger an alarm if any equipment showed an abnormal change in speed. It was a simple, affordable fix that prevented incidents from happening.

Find out how to improve material handling

Control Concepts, Inc. has helped thousands of plants around the world improve bulk material handling. We have worked with every industry, with clients that include both S&P companies and SMEs. Contact us to get a customized proposal for your process.

What Materials Are Prone to Problems in Material Handling?

material flowing

One of the most common problems in material handling is how to get material to flow properly. Many materials have a tendency to clump, cake, or interlock during storage or mixing. That can impact the entire production process, and lead to unnecessary costs and safety issues.

Types of material blocks

Some materials have cohesive properties that cause particles to stick together. This can lead to bridging or ratholing.

During bridging, the material forms an arch above the outlet of the silo or hopper. The particles interlock and bond together because of cohesive strength and internal friction, while the wall friction holds up the ends of the arch.

During ratholing, the material adheres to the container sides, so the flow is limited to just above the container outlet. As more material flows through and accumulates on the walls, the block becomes bigger and more compact.

Bridging and ratholing can lead to all sorts of problems with bulk material handling. It slows down production, causes material waste, and compromises the formula’s consistency and quality. And if workers have to clear the blocks manually—by hammering or even climbing down into silos or hoppers with pick axes—they’re at risk for injury and unnecessary exposure to the material.

Problematic powders

About 50% of manufactured materials use powders at some stage of production. However, many powders are cohesive, which means they have a tendency to cake or become compact under their own mass.

Food ingredients

Some powders like flour have “easy” flow properties; any chunks can be broken apart with gentle aeration. However, heavier powders like cocoa, lecithin, whey, milk, sugar and sweeteners, spices, or even binders and preservatives will form solid, rock-hard chunks.

The food industry also needs to achieve first in/first out flow to avoid stagnant material that can spoil, thus compromising the product’s safety and breaking strict regulations on sanitation and hygiene.

Spoiled material and off-spec batches need to be thrown away, and even a single “bad batch” that escapes quality control can lead to product recalls.

Pharmaceutical powders

An estimated 60% of pharmaceutical sales come from powder formulations such as tablets, capsules, sachets, or inhalable powders.

During processing, pharmaceutical powders will go through several phases where they are exposed to moisture and air. These environmental factors—and variables in properties like size, shape, and texture—affect the flow properties, density, compressibility, and permeability.

These can pose numerous problems in material handling that must be managed well to ensure product efficacy and safety. Pharmaceuticals rely on precise measurements and proportions of ingredients. Material blocks can ruin an entire batch, and lead to material waste or even product recalls.

Grain products

One of the most common problems in material handling arises when conveying grain products from storage silos or bins. The materials may have sat motionless for days or even weeks, and have settled and become more compact. So, their flow properties are very different from powders or granules in aerated samples.

Some examples of common grain products are cornstarch, wheat bran, polenta, tapioca, couscous, rice, and hops. These are used in the food, pet food, beverage, nutraceutical, cosmetic and biofuel industries.

Cement powders

Cement uses many types of powders, including limestone, chalk, glass powder, and steel slag powder (SSP). Sometimes, granite powder is used in place of sand.

These materials all have unique flow properties, and the challenges increase when they are mixed and become sticky, moist, and heavy. Many cement plants have issues with materials bridging over silos and hoppers, which can slow down production speed and vessel capacity by as much as 80%.

Chemical powders

Many industries use chemicals either as a main material, or as a binder, preservative, or enhancer. For example, rubber tire manufacturers use carbon black to improve durability and performance. Battery manufacturers use lithium chloride and carbonate.

These chemicals can cause problems in material handling if they have a high moisture content, or have high cohesive properties. Some materials like carbon black tend to fluidize, forming deposits along the conveyor lines and storage vessels. Since it does not dissolve in water and solvents, cleaning can be time-consuming and expensive.

AirSweep solves problems in material handling

Leading companies in different industries rely on AirSweep to prevent bridging, ratholing, and other problems in material handling. Each nozzle emits a high-pressure, high-volume, 360-degree burst of compressed air to lift and sweep stalled material back into the flow stream – clearing the way for higher factory and material handling efficiency.

You can also contact us to get a personalized consultation on how AirSweep can solve the specific problems in material handling that you encounter in your plant.

Top Challenges for Material Handling in the Candy Industry

material handling challenges with candy

Life isn’t always sweet for the candy and confectionary industry. The industry works with many materials that are prone to bridging, ratholing, and material blocks. Without a good flow aid, production can stall and end up in a big, sticky mess. We will review the top challenges for material handling in the candy industry.

Most common challenges in material handling

Candy and confectionary can use many different materials, ranging from powders to oily or moist solids, small particles to large pieces of nuts, or brittle.

These materials have unique characteristics that can affect material flow and production.

  • Free flowing and non-free flowing powders. While some flow freely from the force of gravity, others have more cohesive properties and are prone to packing during storage, and bridging and ratholing during production.
  • Moist, oily, or sticky liquids and solids. These include raw materials like honey and end-products like caramel. Some materials have a tendency to cake and smear on vessel walls; others can crystallize or thicken under certain plant conditions, further inhibiting material flow.
  • Blends and mixes. These can have ingredients that are different sizes, shapes, and densities. Aside from sticking to the sides of the vessel, the mix can segregate and compromise batch uniformity.
  • Hygroscopic materials. These have a tendency to attract and retain moisture, which leads to clumping and caking during storage and mixing.
  • Corrosive materials. The food industry uses concentrated acids, chlorides, and chemicals like sodium bisulfite and sodium sulfite. Aside from this, the food industry uses hot steam and chemical solutions to clean vessels and meet sanitation standards. This highly caustic environment means that the vessels—and any attached material flow aids—have to be made of materials that resist corrosion.
  • Abrasive materials. Grains and hard crystals like polyols can wear down vessel walls.
  • Perishable materials. Almost all materials used in making confectionaries are easily spoiled and contaminated and need both careful handling and first-in/first-out material flow.

Best flow aid for the candy industry

AirSweep is the best flow aid for tough materials. The powerful air pulses can handle cohesive powders and even moist, oily, and sticky mixes. It is used by food manufacturers around the world, many of whom switched to AirSweep because it performed better than vibrators, fluidizers, and other flow aids.

R. M. Palmer, a candy manufacturer in Pennsylvania, produces specialty holiday confections for US and international distribution. It uses a fine cocoa powder with 12% oil content, which caused bridging and ratholing in the hoppers and required manual cleaning every three to four days.

After installing AirSweep, the plant went from downtime every 3 or 4 days to “no breakdowns, replacements, or any problems whatsoever.” They were even able to add two production shifts per month, increasing productivity and profit margins so much that they were able to recover the cost of the system in just two months.

“AirSweep works,” he said. “It has a stronger air pulse than the bin aerators or fluidizers we previously installed. The air moves the powder down in a very large column so powder doesn’t stick to the walls.”

5 benefits of AirSweep for the candy industry

AirSweep’s unique construction also makes it ideal for the unique conditions of the candy and confectionary industry.

  • Guaranteed on-demand, first-in / first-out flow prevents material stagnation and spoilage
  • USDA-accepted design meets the strictest standards for sanitary equipment
  • Air-tight nozzle snaps shut after each pulse, preventing fine powders and dust from entering the system
  • Durable finish resists abrasion and corrosion and can be safely cleaned with chemical agents
  • Fast and easy assembly allows the unit to be removed for cleaning without any special tools

Get a customized proposal for your process

AirSweep is used in thousands of plants around the world and has solved many challenges in material handling that other flow aids could not. Contact us to find out how you can improve your material flow.

AirSweep, DAZIC & AcoustiClean: Integrated Solutions for Bulk Product Handling

bulk material on conveyer

The production process involves several interconnected steps. Any problems in one stage often create a domino effect, causing more delays and incurring more costs. Control Concepts, Inc. offers proven bulk product handling technology that improves plant efficiency and productivity that can be used individually or integrated to reduce downtime, material waste, and safety hazards.

AirSweep for on-demand material flow

Poor material flow can lead to several problems that can affect a plant’s productivity and a company’s bottom line.

  • Lower productivity. When the flow stops, so does the entire production line.
  • Smaller vessel capacity. Stagnant material can reduce the amount of material that can flow in and out of the vessel.
  • Material spoilage and waste. Inconsistent material flow can lead to stagnant and spoiled material or inconsistent batches that need to be thrown away.
  • Worker safety hazards. Workers have to manually clear material from vessels and may be unnecessarily exposed to hazardous materials.

Prevent these problems with AirSweep. It releases powerful air pulses that push material into the flow stream, leading to steady, on-demand flow.

AirSweep is proven effective for materials with challenging flow properties, such as powders that tend to clump or moist and sticky mixes that stick to vessel walls.

Many customers say that AirSweep was the only flow aid that worked for them—they tried fluidizers, vibrators, and air cannons, but still had to manually clear material. But once they installed AirSweep, they never had to worry about material blocks again.

DAZIC for preventing material pile-up

Many processes involve moving tons of material at a time. If any of the equipment malfunctions, that could mean massive spillage—and a mountain of problems.

  • Days of downtime. Equipment must be turned off until the material pile-up is cleared. Workers have to manually clear the material, or sit around and wait until production resumes.
  • Material waste. In some cases, the material is too contaminated to reuse and must be thrown away.
  • Safety hazards. Workers may be exposed to toxic or hazardous materials.

DAZIC zero speed switches can help prevent material pileups and detect machine failure. They are attached to rotating shafts and send an alarm when there is an abnormal change in rotation speed.

DAZIC speed switches are affordable, efficient, and durable. Many clients are still using the switches they installed over a decade ago, and have never had any incidents of material pile-ups.

The speed switches can be installed on any equipment with a rotating shaft, such as rotary valves, bucket elevators, belt and screw conveyors, saw blades, and drive motors.

AcoustiClean for clearing powder build-up

Powder build-up can clog pipes and affect equipment efficiency, and even create potentially flammable environments. Manual cleaning takes too long, and may even be impractical or impossible for some plant set-ups.

AcoustiClean sonic horns can clear powder build-up quickly and easily—and will never damage even fragile equipment. It releases sound vibrations that can disperse particles even in blind spots that mechanical blowers and rapping systems miss.

Integrated solutions for maximum plant efficiency

AirSweep, DAZIC, and AcoustiClean can work together to control material flow, clean residue, and prevent build-up—as seen in this diagram of a co-gen plant.

AirSweep, DAZIC, and AcoustiClean co-gen plant diagram

Find the right bulk product handling system for your needs

Control Concepts, Inc. can customize a bulk product handling system for your particular material, vessel, and process. Contact us so we can discuss your needs and provide you with a customized diagram.

3 Types of Material Blocks that Slow Down Production

material block in production

In the manufacturing process, production speed and product quality heavily depend on reliable material flow. That means materials flow smoothly, in a first in/first out pattern. However, bulk materials have a tendency to clump together, cling to vessel walls, or form large material blocks that restrict the discharge outlets. Flow can slow down, or even stop completely. Here are the most common types of material blocks, and the only flow aid you need to prevent them.

Bridging / arching

As the name implies, materials form a large bridge or arch right above the vessel outlet. This happens when the particles interlock and bond together, and need an external force to break it up and restore the flow.

There are two types of bridging or arching:

  • Interlocking arch. The particles mechanically interlock, like pieces of a jigsaw puzzle.
  • Cohesive arch. The particles are bonded together because of moisture, temperature, or the concentration of fines.

The strength of the bridge or the arch depends on the material’s inherent cohesive strength and the internal friction of the particles. For example, very fine powders like flour may respond to gentle aeration. However, cocoa powder or titanium dioxide—which has a tendency to clump and aggregate—will need more powerful, concentrated air pulses.

Ratholing

Ratholing occurs when materials accumulate along the vessel walls, leaving only a small flow channel right above the outlet. This creates two problems: the flow slows down, and stagnant material stays in the vessel. Without first in/first out flow, manufacturers run the risk of spoilage and contamination.

Furthermore, if the material has cohesive properties, it will cake and agglomerate instead of flowing out of the vessel. Eventually, the channel closes up and the flow completely stops.

Particle segregation

Granular materials can segregate because of differences in size, shape, and density. This can occur during crushing and grinding, transportation, storage, and mixing.

Segregation is especially critical in the chemical, pharmaceutical, and food industries when materials must be mixed in exact proportions to protect product integrity. For example, a supplement needs a precise balance of vitamins and minerals that is declared on the nutrition label—otherwise, the company could be slapped with a fine and be forced to recall entire batches that don’t meet the specs.

The “perfect” material flow

The gold standard of material flow is mass flow, which has the following characteristics:

  • Steady, uniform flow with a consistent bulk density
  • First in / first out – no stagnant material
  • Controlled discharge rates with no issues of stopping or flooding

AirSweep: achieve reliable material flow

AirSweep is a pneumatic flow aid. It uses powerful, 360-degree air pulses to break apart material blocks and sweep material back into the flow stream.

And when material flows, so do productivity and profits.

  • Reduce downtime from manually clearing material blocks or flushing vessels between product batches
  • Improve product consistency and quality by preventing stagnant material and segregation
  • Avoid material waste from throwing away contaminated material or inconsistent batches

AirSweep also lowers maintenance costs, because it uses less energy and does not damage vessels like other flow aids such as vibrators and fluidizers.

Get a customized proposal for your process

There is no “one size fits all” setup to prevent material blocks. We can customize an AirSweep system where nozzles are positioned at the right place, and release the right sequence of pulses, to move material efficiently.

Contact us to find out more about how AirSweep works, and how it can help improve your process.

Why is AirSweep Effective for Mined Materials?

Coal and mined materials in hand

Mined materials are one of the most critical components of the manufacturing industry. They are used to make thousands of commodities, from automobiles to electronics, and even medicines and household cleaning products. The mobile phone alone uses 42 different minerals—not including what is used for its packaging (paper and plastic need minerals, too!)

You can mine it… but can’t you move it?

However, mined materials have poor flow properties that can pose challenges during storage, processing, and packaging.

For example, hydrated lime—one of the most common components of cement production—is sluggish and has a tendency to pack, bridge, or rathole.

Wet materials such as damp sand or Diatomaceous earth can cling to vessel walls and plug the outlets.

Minerals with irregular particles can also segregate if they have a different hardness, grade, or size. Even after they are carefully screened and processed to a more consistent form, the particles can still interlock.

The best flow aid for mined materials

It’s important to choose a flow aid that can handle mined materials’ unique characteristics. Fluidizers can only activate powders that respond to light aeration. Vibrators can cause some minerals to become more compact. Air cannons still leave residue on vessel walls, and the air tends to “channel” through holes in the material, greatly diminishing effectiveness.

That’s why many companies switched to AirSweep. The powerful air pulses can improve the flow of any mined material—from fine powders to heavy rocks.

AirSweep increases productivity

A leading processor of industrial minerals handles more than 120,000 tons of material every year. However, their biggest challenge was transferring the processed material. It took over an hour to fill one supersack, and workers still had to hammer the vessels.

AirSweep cut that filling time from one hour to two minutes—a 3000% increase in productivity. Production volume increased to the point that an additional forklift driver was hired to keep up with the output.

AirSweep saves money

A cement company had issues with shale clogging the silos. They tried air knockers and vibrators, but workers still had to manually clear the vessels—losing $12,000 per hour of downtime.

AirSweep was the only flow aid that cleared all material build-up, and it used half the energy of air knockers. Since the cost per KWH was very high in their country, the electricity savings alone brought a great return on investment.

The proof is in the flow

AirSweep is used in thousands of plants around the world and has been proven effective for even the most problematic mined materials. Watch this material flow test on powdered hydrated lime.

AirSweep in the mined materials industry

Visit this page to find more case studies and videos on how AirSweep is being used to activate mined materials or contact us for more information and a customized quote.

5 Top Technologies for Automated Bulk Material Handling

Automated technology moving materials

Bulk material handling is an essential part of any industrial or manufacturing process. Raw materials must be delivered to a factory, unloaded into storage facilities, and then poured into silos, hoppers, and other vessels for processing. Automated bulk material handling can make these processes more efficient. Here are some of the latest technology that can help move material in a faster, safer, and even cheaper way.

Automated guided vehicles (AGVs)

AGVs are self-propelled vehicles that can move large volumes of material along a defined pathway, like receiving to the warehouse or straight to the production lines. They can replace manually-operated forklifts and carts, or be used in areas that can’t be reached by conveyor systems.

The AGVs are guided by software and sensors. They can be programmed to run at specific times or stages during the production cycle so that materials are delivered whenever they are needed, without interruption.

There are many different kinds of AGVS: forklifts, carts, towing vehicles, and unit load handlers for small items.

Automated Storage & Retrieval System (AS/RS)

AS/RS systems handle, store, and retrieve materials in warehouses and other storage facilities. This can include automated carousels, vertical lifts, shuttles, and other machines that can lift heavy loads.

AS/RS can maximize storage space, reduce damage to products, and improve inventory control. Since fewer people are required to move items, companies can also tighten security and limit who can access the warehouse and other storage areas.

Warehouse Tracking

Warehouses need to follow a first in/first out system so that materials don’t spoil. However, new shipments are usually placed on top of the stack, so it’s hard to track where the oldest materials are.

Smart warehouse technology systems use coordinated routing, tracking, and control systems to show employees which box or bag must be used next. This includes a consolidated Warehouse Management System (WMS), automated picking tools, and automated inventory control platforms.

Aside from preventing spoilage, these new bulk material handling technologies reduce the cost of manpower and improve demand forecasting.

Machine Monitoring

Machine monitoring prevents shutdowns caused by machine failure.

Sensors alert operators of any problems in mixers, grinders, or conveyors. For example, the material got wet and stuck to the machine, or the scales malfunctioned and overloaded the vessel.

Sensors can also detect vibrations, unbalanced loads, and temperatures of the bearings. While it won’t be able to diagnose the problem, automated monitoring allows operators to troubleshoot and do preventive maintenance.

The sensors are actually required in industries that work with fine powders or other flammable materials that could be ignited by excessive friction in machine parts.

Some sensors have been around for more than a decade, and are proven effective in preventing plant accidents. DAZIC zero speed switches can be attached to conveyors, bucket elevators, and other equipment in a material conveyor system. It detects abnormal changes in speed that could lead to material pileup.

Material flow aids

Poor or irregular material flow slows down production and compromises batch consistency. Stagnant material can also lower the storage capacity of silos and hoppers and may deteriorate and spoil.

Traditionally, workers would have to manually clear material with hammers and pick-axes. However, modern material flow aids like AirSweep can prevent material blocks from occurring.

AirSweep releases powerful air pulses that move stagnant material back into the flow stream. It can be used during processing to ensure first-in / first-out flow, or after processing to flush the vessels clean before the next batch.

Here’s how the AirSweep system allows automated bulk material handling:

Contact us to find out more about AirSweep and other products that can improve your bulk material handling.

What Causes Material Bridging in Hoppers and How AirSweep Can Help

material bridging inside of hopper

Material bridging in a hopper can slow down production and reduce bulk storage space. The stagnant material can spoil or become contaminated, and workers have to clear the vessel and throw out compromised batches.

What is material bridging?

Bridging is the material block that forms above the discharge outlet of a hopper, silo, or any bulk material handling equipment.

The bridge is caused by friction on the vessel walls which slows down the flow of material. Eventually, the material particles start to bind and interlock, until it partially or completely blocks the discharge outlet.

The bridge is so strong that it can support the weight of material above it. New material can condense the trapped material further and strengthen the bonds.

Types of material bridging

  • Mechanical bridging. Particles mechanically interlock, like jigsaw puzzles. This usually happens for particles that are larger than 3mm.
  • Cohesive bridging. Particles compress until they bind together. This usually happens for smaller particles, especially those that attract moisture.

What causes material bridging in the hopper?

Material bridging can be caused by the hopper design, the material’s flow properties, and the conditions in the plant.

Hopper Design

Ideally, the hopper design should reduce friction and encourage flow. However, there is no one-size-fits-all solution. Solids and liquids behave differently, and materials have unique properties that can also vary in different conditions. These factors have to be considered while choosing the hopper’s angle, and the outlet’s shape and diameter.

Material Properties

Some materials are simply more prone to bridging and arching. This includes:

  • Moist and sticky materials
  • Materials that tend to settle during storage
  • Materials with a high cohesive strength
  • Hygroscopic powders that attract moisture
  • Pellets that soften and form soft clumps
  • Fibers that can entangle
  • Irregular particles that can interlock
  • Heavy materials that can push down on stagnant material and cause it to compress

Plant Conditions

Fluctuating temperatures can affect the stress on the hopper walls and the material flow properties. Moisture in the air can cause materials to expand and compress. Gas in the air can also permeate through powders and fill empty spaces.

The best solution for material bridging in the hopper

Flow aids solve bridging and other material blocks by breaking up the cohesive bonds in the material. However, not all flow aids can do this safely or effectively.

Manual cleaning—where workers hammer the vessel or enter the hopper to clear the build-up with axes and shovels—is slow and dangerous. Some materials release flammable or toxic gases during storage. Workers are also at risk for falls, sprains, health problems from direct exposure to the material, or being hit by falling material.

Vibrators can damage the vessel and can cause some materials to become more compact. Fluidizers can only activate light powders; air cannons are expensive and still leave material residue on walls.

AirSweep is the most cost-effective solution for material bridging in hoppers. It releases powerful air pulses that break up bridging and sweep stagnant material back into the flow stream.

AirSweep engineers customize the system so the units are installed at key areas on the hopper to stimulate first-in/first-out flow. They select the right model for the material and the vessel size. The AirSweep USDA-accepted model is also specially designed for sanitary applications like food, beverage, and pharmaceuticals.

The AirSweep system is energy-efficient. It uses less air than air cannons, and the units pulse in sequence instead of running continuously like vibrators and fluidizers. The units also have a large area of activation and move more material with every pulse.

Find more information about AirSweep, or get a customized quote.